Metallurgical furnace.



L. ADDIOKS & G. L. BROWER. METALLURGIGAE FURNACE.

APPLIGATION FILED MAY 22, 1913.

1 03,719 Patented Jan.6,1914.

Z SHEETSSHEET 1.

INVENTORS v "ul ITNESSES: M

L. ADDIOKS & G. L. BROWER.

METALLURGIGAL FURNACE.

APPLICATION FILED MAY 22, 1913. LQSJH 9., Patented Jan. 6, 1914.

2 SHEETS-SHEET 2.

a? 3% x W v m INVENTORS I Owflmca WITNESSES: fiu

ATES

AMBQY, AND CLARENCE L. BROWER, OF CHROME,

NEW JERSEY.

ran'rannuaercan FURNACE.

Specification of Letters Patent.

Application filed May 22, 1913. Serial No. 769,176.

Patented Jane, an.

To all whom it may concern:

Be it known" that we, LAWRENCE Annions,

residing in Perth Amboy, in the county of Middlesex and State of New Jersey, and CLARENCE L. -BROWER, residing in Chrome, in the county of Middlesex and State of New Jersey, both citizens of the United States, have jointly invented certain new and useful Improvements in- Metallurgical Furnaces, of which the following is a specification.

. This nvention relates to furnaces for use chiefly in copper refining. For this purpose reverberatory furnaces are used.

\ how Our invention provides a basic-lined furnace for use in copper refining, smelting, 0r analogous processes. Instead of lining the furnace with silica brick with a dished bottom or hearth of such brick or with a flat bottom of sand, we construct the furnace with a bottom or hearth of magnesia brick and the side walls and roof of chrome brick.

Other features will be explained as the de scription proceeds.

In the accompanying drawings illustrating our improved furnace,l?igure 1 is a vertical longitudinal mid-section; Fig. 2 is a horizontal section; Fig. 3 is a transverse section; Fig. d is a fragmentary pers ective view, in section through the tap-ho e and channel.

Referring to the drawings, A is the foundation bed, which is made preferably solid of concrete or masonry. Preferably the base is of concrete A overlaid with a masonry bed B which may be of red brick. The hearth D of basic brick is made concave as an inverted arch, and to support this the solid bed is made concave preferably by buildbrick in two courses,,the lower course C being laid with a concave top, and the upper concave floor or inverted arch of the furnace course C beinglaid on this as an inverted arch.

The hearth D is of magnesite brick, and of lighter specific gravity than the meta to be treated, it tends to float up and to admit the metal beneath it, and to resist this is laid as an inverted arch between skewbacks d d which receive the thrust and communicate it to the side supports of the furnace.

.: over the roo neath the hearth through pipes aid in the thrust from the opposite half of the inverted The side walls E E are of chrome brick. To properly support the side walls and protect the skew-backs d, a special construction 1s provided, shown best in Fig. 4, the brick of ,the concave hearth D being continued beneath the wall to theskew-back, thelatter being beneath the wall and preferably flush with its outer side. The bricks a beneath the wall are. extended above the line of the hearth and terminate with a practically flat upper face serving as a suitable base on which to build up the side wall. Thus the spring of the hearth is resisted directly by the skew-back'irrespective of the outer wall,- the latter is iven a firm foundation, and the skew back 1s protected from contact with the metal and from injury by heat. The arched roof F is also of chrome brick, its thrust being taken against skew-backs f f which communicate the thrust to the side supports of the furnace. v

The furnace is preferably en orted laterally by the usual buck-stays if H, preferably backed by horizontal beams as usual, and held together by tie-rods b b passing and by tie-rods e e assing bemasonry bed A. These t1erods are pro- 86 vided with the usualadjusting nuts for permitting the slacking ofi' of the buck-stays as the furnace roof and hearth expand in heating up the furnace.

The furnace has the usual flue G, which is also best built of chr'ome brick. It has also the usual side doors J Jv for use in charging and blowing, and the usual end door K beneath the flue for use in skimming and polmg. so

The end door K may be made low enough to serve as the tap-hole, but we prefer to tap through the side wall. This necessitates the formation of a lateral channel M through the on one side of the center, its bottom line tan- 1 genting the arch at the center. This channel may be made of the width of a single course of bricks, which serve to transmit the arch to the side plate 9. The channel leads to a tap-hole P formed in the side wall of the furnace. The furnace hearth inclines toward the channel, so that the metal-will flow mortar 'ofmagnesite dust, with a suitable the'furnace is to laythe brick with a suitable mortar or cement, adapted to bind the basic brick into a solid substantially monolithic mass. For this purpose we employ a thin binder, preferably silicate of sodium solu- 7 tion.

, The construction described produces a basic-lined reverberatory furnace, the success and permanence of which we have abundantly demonstrated in actual practice. Such a furnace has for copper refining many practical advantages. I

Copper refining has heretofore been cornmonly performed in a silicious furnace having side walls of silica brick, and a bottom.

of silica brick or of sand, with usually a cooling vault beneath. The silicious lining furnishes silica which with the cuprous oxid in the copper forms a silica slag which has to be removed'for treatment in a blast furnace. Should the charge contain impurities which when oxidized have a very strong 'aflinity for silica, the danger to the furnace is severe and frequently causes failure of the bottom, which allows the charge to run into thecooling vault. Various expedients have been resorted to to prevent the failure of the silicious walls or bottom due to the inability to control the extent of erosion or slagging of the silicious material. y

In copper refining, three classes of material are ordinarily dealt with,'namely (1 tofore this work has either been done in a basic furnace on a small scale where prob lems of construction do not seriously enter,

or the material has been diluted by the addition of large quantities of relatively pure copper to bring it above the danger zone. The basic furnace enables this class to be treated by itself, thereby avoiding introducing impurities into the large quantity of diluent and correspondingly increasing the degree of their elimination, and ,it is always possible to remove a greater ercentage of anielement by scorification w on that element is" present in quantity. Also the impurities are concentratedin a'much smaller bulk of slag, thereby facilitating their recovery, if 0 value. Finally the charge-can be worked thoroughly as there is no fear of resulting danger to the furnace.

foul, such as secondary metallurgical pro (2) When ordinary blister co per is treat;

ed in a silicious furnace, about our per cent. of the weight of the charge slagis formed, while the quantity necessary to carry off the impurities is far less than this figure. Some silica is desirable to form the necessary slag, but sufiicient is present in the bullion itselfand in the ash from the charcoal or coke, poles, etc., used in the preceding charge.

(3) Pure material, such as cathodes, require with the basic furnace but a simple melting, whereas under silicious practice the same cycle of operations with production of about three per cent. of slag is gone through withas in the case of blister copper. Our basic furnace makes possible the practical suppression of-slag. In actual practice it is indicated that the slag made in ordinary cyclic operation will not exceed one-half per cent. Ordinarily the elimination of the refining and making but a melting with suifi cient poling to reduce the on rous oxid un-- I avoidably formed while meltmg, will be all that is necessary. Any slag made can ordinarily be charged back with the next melt. The basic furnace also renders conceivable the continuous operation of the reverbratory by ,extension of the principle laid down in Patent No. 980,584 of January 3, 1911.

It is possible that other basic materials than magnesite brick may be used-as the furnace hearth, and that'other basic or neutral materials than chrome brick may be used for the side walls and roof; but these are practicable refractory materials for the purpose of our invention and have given satisfactory results.

Certain features of construction of our furnace are applicable with other lining or refractory materials than those named.

Our furnace may be otherwise modified according to the particular urpose in view, as will, be well understood by metallurgists and furnace men.

The improvement in the refinin or melting of copper which is attainable y the use of our furnace is not herein claimed, being arate application for patent.

To provide for the expansion of the roof in longitudinal direction, expansion joints h k are provided at intervals, covered onthe exterior by bands 2' 11 of refractory material.

Those features of the furnace which are shown in the drawings but are not described, are of well known construction, and form no part of our invention.

. We claim as our invention 1. A metallurgical furnace having a magnesite hearth and chrome roof.

2. A metallurgical furnace having a hearth of magnesitc, and walls and roof of chrome.

3. A reverberatory furnace having a concave hearth of magnesite brick, and a roof of chrome brick.

oser/1e v w I 4:. A metallur 'cal furnace having a lin- 6. A reverberatory furnace having a.

hearth of basic brick laid as an inverted arch, between cast-iron skew-backs and said hearth beneath the. side walls laid with bricks to form at their tops with said skew-v backs a practically level support for said side walls.

7. A reverberatory furnace having a hearth of basic brick laid as an inverted arch, and

said arch beneath the side walls laid with.

- longer brick projecting above the surface of the hearth and forming a practically level top on which to lay the side walls.

8. A reverberatory furnace having a hearth I of basic brick laid as an inverted arch, with metal skew-backs receiving the thrust of such arch, the basic bricks under the side walls terminating in a level top, and the side walls built up on such'level top and on the skew-back.

9. A reverberatory furnace having a concave hearth of brick forming an inverted arch and having a side tap-hole, said hearth formed with a transverse channel leading from ,the middle thereof to said tap-hole, said channel laid of brick which reslst the thrust of the opposin half of said arch, and means for reslstin tie spring of said arch and of said channe beneath the tap-hole.

In Witness whereof, we have hereunto si ned our names in the presence of two su scribing witnesses.

LAWRENCE ADDICKS.

CLARENCE L. BROWER. Witnesses:

' SIDNEY ROLLE,

EDWARD J. BULFIN. 

